How is the RAM/HDD of a new workspace determined?



I’m wondering how can one determine the RAM/HDD size of a workspace at the time of creation, and possibly change it later?

I noticed some of my workspaces are 512MB/2GB, while two of them are 1GB/5GB. For some machine learning tasks I need large HDD, while I general I prefer more RAM. Do I have any control over it?

There is a way to resize the workspace, but it works only for premium accounts, which I’m not.